Jetty session cluster session attribute

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Jetty session cluster session attribute

nndd
Hi there,

I am following the following document to configure jetty session cluster: http://docs.codehaus.org/display/JETTY/Session+Clustering+with+a+Database

And use Apache httpd as the load balancer.

One thing is confusing me is: session attribute is persisted to the database, then shouldn't all the cluster nodes read the same session attribute? In my set up, this is not the case. Each cluster node maintain its own session attribute. That says the session attribute is consistent on every node, but not across nodes. Another thing I noticed is that the last node and other relevant columns of the persisted session attribute are only updated in database when one of the two nodes handled the request. The information of another nodes seems to be stored in memory?

Both of the nodes hold the same session ID, although different session object.

Is this expected behavior or my configuration is wrong? If configuration is wrong, where can I find more documentation about the config?

Thanks a lot,
Sarah
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Re: [jetty-users] Jetty session cluster session attribute

Jan Bartel-3
Sarah,

The database is updated as info in the session object changes.
Although, we do do a few optimizations to limit the amount of updating
that occurs, to prevent hammering the database. When a session is
in-use on a node it is in-memory, and the database updated when the
session changes. When the session migrates to a new node, the session
is (re-)read into memory from the database. If you are seeing
inconsistencies, the only scenario I can foresee is if your session is
bouncing around a lot between nodes, rather than using
sticky-sessions.

Jan

On 8 June 2012 19:52, nndd <[hidden email]> wrote:

> Hi there,
>
> I am following the following document to configure jetty session cluster:
> http://docs.codehaus.org/display/JETTY/Session+Clustering+with+a+Database
>
> And use Apache httpd as the load balancer.
>
> One thing is confusing me is: session attribute is persisted to the
> database, then shouldn't all the cluster nodes read the same session
> attribute? In my set up, this is not the case. Each cluster node maintain
> its own session attribute. That says the session attribute is consistent on
> every node, but not across nodes. Another thing I noticed is that the last
> node and other relevant columns of the persisted session attribute are only
> updated in database when one of the two nodes handled the request. The
> information of another nodes seems to be stored in memory?
>
> Both of the nodes hold the same session ID, although different session
> object.
>
> Is this expected behavior or my configuration is wrong? If configuration is
> wrong, where can I find more documentation about the config?
>
> Thanks a lot,
> Sarah
>
> --
> View this message in context: http://jetty.4.n6.nabble.com/Jetty-session-cluster-session-attribute-tp4958607.html
> Sent from the Jetty User mailing list archive at Nabble.com.
> _______________________________________________
> jetty-users mailing list
> [hidden email]
> https://dev.eclipse.org/mailman/listinfo/jetty-users



--
Jan Bartel <[hidden email]>
www.webtide.com – Developer advice, services and support
from the Jetty & CometD experts.
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